1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
|
# This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.
from __future__ import absolute_import, division, print_function
import json
import os
import subprocess
import sys
import textwrap
import pytest
from cryptography.hazmat.bindings.openssl.binding import Binding
MEMORY_LEAK_SCRIPT = """
import sys
def main(argv):
import gc
import json
from cryptography.hazmat.bindings._openssl import ffi, lib
heap = {}
@ffi.callback("void *(size_t, const char *, int)")
def malloc(size, path, line):
ptr = lib.Cryptography_malloc_wrapper(size, path, line)
heap[ptr] = (size, path, line)
return ptr
@ffi.callback("void *(void *, size_t, const char *, int)")
def realloc(ptr, size, path, line):
if ptr != ffi.NULL:
del heap[ptr]
new_ptr = lib.Cryptography_realloc_wrapper(ptr, size, path, line)
heap[new_ptr] = (size, path, line)
return new_ptr
@ffi.callback("void(void *, const char *, int)")
def free(ptr, path, line):
if ptr != ffi.NULL:
del heap[ptr]
lib.Cryptography_free_wrapper(ptr, path, line)
result = lib.Cryptography_CRYPTO_set_mem_functions(malloc, realloc, free)
assert result == 1
# Trigger a bunch of initialization stuff.
import cryptography.hazmat.backends.openssl
start_heap = set(heap)
func(*argv[1:])
gc.collect()
gc.collect()
gc.collect()
# Swap back to the original functions so that if OpenSSL tries to free
# something from its atexit handle it won't be going through a Python
# function, which will be deallocated when this function returns
result = lib.Cryptography_CRYPTO_set_mem_functions(
ffi.addressof(lib, "Cryptography_malloc_wrapper"),
ffi.addressof(lib, "Cryptography_realloc_wrapper"),
ffi.addressof(lib, "Cryptography_free_wrapper"),
)
assert result == 1
remaining = set(heap) - start_heap
if remaining:
sys.stdout.write(json.dumps(dict(
(int(ffi.cast("size_t", ptr)), {
"size": heap[ptr][0],
"path": ffi.string(heap[ptr][1]).decode(),
"line": heap[ptr][2],
})
for ptr in remaining
)))
sys.stdout.flush()
sys.exit(255)
main(sys.argv)
"""
def assert_no_memory_leaks(s, argv=[]):
env = os.environ.copy()
env["PYTHONPATH"] = os.pathsep.join(sys.path)
argv = [
sys.executable, "-c", "{0}\n\n{1}".format(s, MEMORY_LEAK_SCRIPT)
] + argv
# Shell out to a fresh Python process because OpenSSL does not allow you to
# install new memory hooks after the first malloc/free occurs.
proc = subprocess.Popen(
argv,
env=env,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
)
try:
proc.wait()
if proc.returncode == 255:
# 255 means there was a leak, load the info about what mallocs
# weren't freed.
out = json.loads(proc.stdout.read().decode())
raise AssertionError(out)
elif proc.returncode != 0:
# Any exception type will do to be honest
raise ValueError(proc.stdout.read(), proc.stderr.read())
finally:
proc.stdout.close()
proc.stderr.close()
def skip_if_memtesting_not_supported():
return pytest.mark.skipif(
not Binding().lib.Cryptography_HAS_MEM_FUNCTIONS,
reason="Requires OpenSSL memory functions (>=1.1.0)"
)
@skip_if_memtesting_not_supported()
class TestAssertNoMemoryLeaks(object):
def test_no_leak_no_malloc(self):
assert_no_memory_leaks(textwrap.dedent("""
def func():
pass
"""))
def test_no_leak_free(self):
assert_no_memory_leaks(textwrap.dedent("""
def func():
from cryptography.hazmat.bindings.openssl.binding import Binding
b = Binding()
name = b.lib.X509_NAME_new()
b.lib.X509_NAME_free(name)
"""))
def test_no_leak_gc(self):
assert_no_memory_leaks(textwrap.dedent("""
def func():
from cryptography.hazmat.bindings.openssl.binding import Binding
b = Binding()
name = b.lib.X509_NAME_new()
b.ffi.gc(name, b.lib.X509_NAME_free)
"""))
def test_leak(self):
with pytest.raises(AssertionError):
assert_no_memory_leaks(textwrap.dedent("""
def func():
from cryptography.hazmat.bindings.openssl.binding import (
Binding
)
b = Binding()
b.lib.X509_NAME_new()
"""))
def test_errors(self):
with pytest.raises(ValueError):
assert_no_memory_leaks(textwrap.dedent("""
def func():
raise ZeroDivisionError
"""))
@skip_if_memtesting_not_supported()
class TestOpenSSLMemoryLeaks(object):
@pytest.mark.parametrize("path", [
"x509/PKITS_data/certs/ValidcRLIssuerTest28EE.crt",
])
def test_x509_extensions(self, path):
assert_no_memory_leaks(textwrap.dedent("""
def func(path):
from cryptography import x509
from cryptography.hazmat.backends.openssl import backend
import cryptography_vectors
with cryptography_vectors.open_vector_file(path, "rb") as f:
cert = x509.load_der_x509_certificate(
f.read(), backend
)
cert.extensions
"""), [path])
def test_ec_private_numbers_private_key(self):
assert_no_memory_leaks(textwrap.dedent("""
def func():
from cryptography.hazmat.backends.openssl import backend
from cryptography.hazmat.primitives.asymmetric import ec
ec.EllipticCurvePrivateNumbers(
private_value=int(
'280814107134858470598753916394807521398239633534281633982576099083'
'35787109896602102090002196616273211495718603965098'
),
public_numbers=ec.EllipticCurvePublicNumbers(
curve=ec.SECP384R1(),
x=int(
'10036914308591746758780165503819213553101287571902957054148542'
'504671046744460374996612408381962208627004841444205030'
),
y=int(
'17337335659928075994560513699823544906448896792102247714689323'
'575406618073069185107088229463828921069465902299522926'
)
)
).private_key(backend)
"""))
def test_ec_derive_private_key(self):
assert_no_memory_leaks(textwrap.dedent("""
def func():
from cryptography.hazmat.backends.openssl import backend
from cryptography.hazmat.primitives.asymmetric import ec
ec.derive_private_key(1, ec.SECP256R1(), backend)
"""))
|
